Chip and supply item for imaging device, including communication

ABSTRACT

A supply item has toner for use in an imaging device. A chip has memory storing quanta indicating allowed usage of the supply item over its lifetime and a multiplier correlating the quanta to toner mass. The imaging device requires quanta to conduct imaging operations and loads the quanta and multiplier by way of a certificate stored in the memory. The imaging device retrieves quanta from the chip over time and both devices keep tally. Initialization between the supply item and imaging device includes providing encrypted and unencrypted instances of firmware versions and certificates from the supply item that the imaging device can compare for security. Alternatively, the supply item defines a fuser assembly, imaging unit, intermediate transfer member, or other component installed for use in the imaging device.

BACKGROUND 1. Field of the Disclosure

The present disclosure relates to supply items of imaging devices, suchas toner cartridges, fusers, imaging units, intermediate transfermembers, or the like. It relates further to chips associated with thesupply items and to communications with imaging devices.

2. Description of Related Art

Users replace spent supply items with new ones during maintenance orreplenishment of components or toner in imaging devices. As supply itemsare often configured with a chip storing metrics, identification, orother details about the supply item, there exists a need to communicatethe chip to a controller of the imaging device. The need extends tosecuring communications between the chip and controller and establishingtrust with one another.

SUMMARY

The above and other problems are solved with a chip and supply item foran imaging device, including communicating with a controller of theimaging device. In one embodiment, a supply item has toner for use in animaging device. A chip has memory storing quanta indicating allowedusage of the supply item over its lifetime and a multiplier correlatingthe quanta to toner mass. The imaging device requires quanta to conductimaging operations and loads the quanta and multiplier by way of acertificate stored in the memory. The imaging device retrieves quantafrom the chip over time and both devices keep tally. Initializationbetween the supply item and imaging device includes providing encryptedand unencrypted instances of firmware versions and certificates from thesupply item that the imaging device can compare for security.Alternatively, the supply item defines a fuser assembly, imaging unit,intermediate transfer member, or other component installed for use inthe imaging device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of an imaging device and supply item, including chipfor communication with the imaging device;

FIG. 2 is a diagram of a controller of an imaging device configured on amaster node of an I2C communications bus and multiple chips configuredon slave nodes of the bus, including a supply item;

FIGS. 3A-3C are flow charts of communication between the chip of asupply item and an imaging device to track quanta of a supply item;

FIG. 4 is a bar graph indicating usage over time of a supply item in animaging device;

FIG. 5 is a flow chart of communication between the chip of a supplyitem and an imaging device utilizing a firmware version of the chip; and

FIG. 6 is a flow chart of communication between the chip of a supplyitem and an imaging device utilizing device certificates, including aslave chip of the imaging device.

DETAILED DESCRIPTION

With reference to FIG. 1, an imaging device 8 typifies a printer,all-in-one (AIO) device, multi-function printer (MFP), copy machine,scanner, fax machine, or the like. It produces a hard copy output ofmedia 10 upon processing a copy, fax, or print job. It receives jobsfrom wired or wireless computing connections to a laptop 12, desktopcomputer 13, mobile device 14, fax 16, scanner 18, etc. over a direct orindirect computing connection (N), as is familiar. A controller C of theimaging device, such as an ASIC(s), microprocessor(s), circuit(s),combination thereof, etc., directs the imaging operations from receiptof the job through hard copy output, as is also familiar.

A supply item 20 installs with the imaging device during use. The supplyitem typifies one or more toner cartridges, fuser assemblies, imagingunits, intermediate transfer members (ITMs), or the like. Its housing 22defines a shape accommodating its contents and has a size appropriatefor inserting into an opening 24 of the imaging device. The openingresides externally to the imaging device or internally upon opening adoor 26, for example. The supply item 20 also includes a chip 30. Thechip 30 is configured for attachment to the housing 22 of the supplyitem, or resides elsewhere. When attached, a connector in the imagingdevice electrically contacts the chip 30 to the controller C uponinstallation of the supply item. When not attached, the chip 30 connectsto the controller by way of a direct or indirect computing connection,such as at USB port 31.

In certain embodiments, the chip 30 includes memory 40 having contentsused for processing and may be provided to or made readable by thecontroller upon the issuance of appropriate commands from the imagingdevice. A Map of the memory, readable by humans and corresponding to thecontents of the memory, includes values such as a firmware version (FWV)42 identifying a current version of firmware on the chip. The FWV maytake many forms, but can be listed with numbers and/or letters includingor not decimal points or commas, e.g., DW 1.0, or take any form. Thememory also includes one or more certificates usable to establish trustbetween the chip and the controller and to bundle together items usefulduring processes of certification. The certificates can be issued by amanufacturer or other supplier of the chip, for example, such as adevice certificate 44 (Dev. Cert.) or a manufacturer of supply items andattendant chips, such as supply certificate 46 (SCert). In variousforms, the device certificate 44 bundles together various chipidentifies, such as serial or part numbers of the chip and may includeunique signatures so that items in communication with the chip can trustthe source of the chip. In one instance, the device certificate includesa device unique public key signed by a global key to instilltrustworthiness between devices regarding the contents and security ofthe chip.

In the supply certificate 46, contents may be bundled togetheridentifying features particular to the supply item. The SCert includes,but is not limited to, types 41 of imaging devices in which the supplyitem works, how much quanta (Q) 43 is associated with the supply item,and one or more multipliers (M) 45 that serve as correction factor(s) toassist an imaging engine of the imaging device when conducting imagingoperations. As will be seen below, the quanta indicates an allowed usageof the supply item over a lifetime of the supply item while themultiplier correlates the quanta to a metric related to a type of thesupply item. When the supply item typifies a toner cartridge, the quantaindicates the allowed usage of the imaging toner in the housing 22 ofthe supply item 20 over a lifetime thereof and the multiplier correlatesthe quanta to mass of the imaging toner. The quanta and multiplier areset during manufacturing of the supply item and stored in memory. TheSCert may additionally include items of interest for communication tothe controller of the imaging device, such as a chip identifier 47, thusduplicating or not items bundled in the device certificate or otherwisefound in memory. The Map may also note reference to a starting byte(Ref. Byte and its corresponding Hexadecimal (Hex) mapping) in thememory 40 in which the contents of the memory can be found and itslength (L), in bits, for example. Still other embodiments are possible.

With reference to FIG. 2, the chip 30 of the supply item 20 isconfigured with the controller C of the imaging device by way of asuitable communications system. In one embodiment, the system comprisesan I2C (Inter-Integrated Circuit) communications bus 50. It includesclocking and data lines tied to the controller and chip and power/groundlines (not shown). The chip 30 is configured on a slave node 52 of thebus while the controller C is configured on a master node 54 of the bus.A chip 60 is also configured on the bus as another slave on a slave node56. It resides in the imaging device and can be arranged or not with thecontroller on a common circuit card 61. It functions to provide serviceto the controller as a liaison to the controller by mediating commandsand responses to and from the chip 30 of the supply item. As both chipshave a common heritage and programming understood by one another, theyare able to communicate according to known authentication andencryption/decryption protocols, for example. The chip 60 bundles andreceives communications from chip 30 and verifies or not to thecontroller that responses of the chip 30 are trustworthy. As is typicalof I2C, the controller communicates with its slaves by uniquelyaddressing them and the slaves reply or not according to the address onthe bus. Still other slaves are contemplated for communication with thecontroller as indicated by the ellipses of the bus 50. They include, butare not limited to, chips associated with variously colored tonercartridges in the imaging device, fuser assemblies, imaging units, ITMs,and the like.

The controller C is also configured to connect to traditionalelectrophotographic (EP) components of the imaging device to create hardcopy outputs on media, such as a laser printhead 70. The controllercommunicates with the EP components on a channel 72 and such may befurther used to effectuate or not an enforcement condition on thechannel, such as allowing or preventing imaging operations to occur.Items necessary to the controller to allow enforcement and to generallycommunicate with the EP components and chips on the bus are provided.They include, but are not limited to, applications, programs, keys, andmemory, both volatile and non-volatile. In the non-volatile memory, acertificate 59 (FIG. 1) is stored for access by the controller. Thestored certificate 59 contains features of the various types of supplyitems and their associated chips that may be installed in the imagingdevice and configured on the communications bus. For example, if thesupply item typifies a toner cartridge, the stored certificate 59includes features relating imaging toner of the cartridge to imagingpixels actually produced on hard copy sheets of media imaged by theimaging device. Still other embodiments are possible.

With reference back to FIG. 1, the role of the certificates 46, 59 ofthe supply item and the imaging device are now described to track alifetime of the allowed usage of supply items in the imaging device,especially tracking imaging toner of supply items 20 configured as tonercartridges. At a high level, the tracking of imaging toner consists ofsecure metering between the supply item and the imaging device. Itoperates like a micro-payment system with many small-sizedauthorizations of quanta from the supply item to the imaging devicerepresenting “pay-as-you-go.” The imaging device maintains severalaccumulators to track both “authorized usage” of the supply item,dictated by the quanta and multipliers of the supply and storedcertificates, and actual use or “metered usage” measured by the imagingdevice for each supply item. The metered usage is tracked in real timeas toner is used and sheets of media are printed for each supply item.The metered usage can be tracked as actual pixels imaged on media andthe controller obtains them per the print job being rendered in theimaging device. The controller can also reconcile the imaging pixels tocounts of media pages as flagged by a top-of-page indicator in the printjob. As metered usage gets close to authorized usage, during imaging, itis necessary to request more usage from the supply item via a commandfrom the imaging device stylized as a quanta request. One quanta fromthe supply item gives the imaging device more authorized usage. Theamount of allowed usage in a quanta is derived from parameters set inthe stored certificate 59 of the imaging device 8 and the multiplier 45in the SCert 46 of the supply item 20. To prevent counterfeiters frommerely adding quanta or increasing allowable usage of the supply item,the quanta negotiations between the imaging device and supply itemsoccurs in a quanta decrement-only fashion until the quanta is depleted,thus ending the allowable usage of the supply item. Also, it ispreferred that requests of quanta from the imaging device to the supplyitem take place in a secure fashion. That the supply item and imagingdevice must trust one another, a mutual authentication occurs firstbetween the devices. Additional security consists of authenticating thesupply item to the imaging device in predetermined time periods.

In more detail, a method 300 of FIG. 3A commences upon the installationof a supply item in an imaging device, 302. The chip of the supply itemand the imaging device power up, initialize sessions over the I2Ccommunications bus, and authenticate themselves to one another. Theimaging device then sends to the supply item a request to receive thesupply certificate and loads its contents upon receipt into anappropriate memory, 304. This includes reading and storing from theSCert the amount of quanta for the allowed usage of the lifetime of thesupply item and its multiplier(s). When the supply item is configured asa toner cartridge, a representative SCert includes an initial amount ofquanta Q=4,374 (unitless) and a multiplier correlating the imaging tonerto quanta, in mass, where multiplier M=50 mg of toner/quanta.

It is expected that the initial installation of the toner cartridgecauses spillage or loading of small amounts of imaging toner into theimaging unit of the imaging device. Various calibration routines arealso expected to execute, including printing calibration pages therebyexpending even more imaging toner from the cartridge. As it is preferredthat the controller C allow these actions to take place, and not executean enforcement on the channel 72 of the laser printhead 70 (FIG. 2), forexample, there needs to exist some initial authorized amount of imagingthat can take place by the imaging device, even before the imagingdevice negotiates a first installment of quanta from the supply item. At306, therefore, the imaging device determines an initial authorizedusage (αu) of imaging (in pixels) that can occur in the imaging deviceto conduct calibration and other preliminary functions. That the imagingdevice has general knowledge regarding how much initial imaging needs tooccur, not the supply item, the controller is preconfigured to retrievefrom its own certificate 59 an initial authorized usage (αu) 57 (FIG. 2)of the supply item. In an example, an initialAuthUse=6,881,245 imagingpixels. As seen in FIG. 4, this initial authorized usage (αu) is denotedat time (t0).

Referring back to FIG. 3A, the imaging device next tracks the actualimaging operations of the supply item, known as “metered usage” (mu),308. It does so in the same units as the authorized usage, e.g., imagingpixels, but appreciating when the supply item is configured as a fuserassembly, for example, the units may define numbers of pages of mediasheets. Conversion between units may also exist as imaging pixels relateto media sheets since print jobs typically include a top-of-pagenotifier identifying one printed page from the next. Regardless of form,the metered usage (mu) begins at zero at time t0 as seen in FIG. 4.Thereafter, it increases with printing to some measurable amount at timet1, but is less than the authorized usage (αu) and is relatively faraway. As imaging operations continue, the metered usage increasesrelative to the authorized usage. However, so long as the authorizedusage exceeds the metered usage, 310, and the metered usage remainsrelatively far away from the authorized usage, 314, imaging operationscontinue and the controller tracks imaging at 308.

At 314, however, the metered usage eventually reaches a threshold ofcloseness to the authorized usage as seen at time (t2) (FIG. 4), forexample. The controller then needs to obtain more authorized usage anddoes so by requesting additional quanta from the supply item, 316. Themeasure of closeness to the authorized usage at 314 that triggers therequest for more quanta at 316 is predetermined and stored for access bythe controller as a warning threshold 51 in certificate 59, FIG. 1.Alternatively, the threshold can be stored for access by the controlleron the chip 30 of the supply item, the chip 60 of the imaging device, orelsewhere. In one embodiment, the threshold in certificate 59 is definedas an enforceUseThreshold=10.22M pixels, but any number of imagingpixels can be used.

It should be appreciated, however, that if the controller does notinitiate the request for additional quanta, continued operations of theimaging device causes the metered usage to eventually catch or reach theamount of the authorized usage and the condition αu>mu at 310 remains nolonger satisfied. As such, the imaging device would be forced at 312 totake corrective action. Actions of this type include, but are notlimited to, executing diagnostic routines, throwing errors, settingflags, ceasing functions, repeating calculations or processes, and/orultimately preventing imaging operations via enforcement on channel 72between the controller and the laser printhead or other EP components.

With reference to FIG. 3B, the request by the imaging device for morequanta from the supply item begins with the controller C of the imagingdevice determining how much quanta it requires. The actual amount isvariable dependent on various factors, particularly volume of printingby users or sizes of print jobs. For example, if users of the imagingdevice are imaging hundreds of pages per multiple print jobs per day,the increase in authorized usage, thus the request for more quanta, mustbe made very large in order to prevent enforcement on channel 72 (FIG.2). Alternatively, if users of the imaging device only image one pageper one print job per week, increases in the authorized usage can bemade in much smaller amounts and made less frequently. Alternativelystill, the request for quanta can occur in predefined increments, suchas small percentages (e.g., 1%) of the original amount of quanta of thesupply certificate, e.g., the micro-payment. Still other embodiments arepossible.

Regardless of amount, the controller of the imaging device formulates acommand for additional quanta 318 and such is packaged for delivery tothe slave chip 60 of the imaging device. Upon receipt, the chip 60 takesseveral steps to formulate a challenge to the chip 30 of the supplyitem. First, the chip 60 undertakes encryption of the quanta command.This includes first generating a nonce, 320. The nonce can be of anysize. Next, the nonce is encrypted, 322. This includes symmetricencryption, such as AES (Advanced Encryption Standard) or TDES (tripledata encryption standard) encryption. It includes key whitening, or not.The chip 60 does this at least once, but may encrypt and key whiten foras many times as the system dictates. At 324, the chip 60 thenformulates the challenge for quanta of the chip 30 of the supply itemand sends that, the encrypted nonce, and a select plurality of bits fromthe nonce (unencrypted or ‘in the clear’) back to the controller forsending to the chip 30 of the supply item. The unencrypted select bitscan be of any size and selected anywhere in the nonce, such as thebeginning, end, or middle. The controller then reads the package fromthe chip 60 and forwards it to the supply item, 326. The controller alsostarts a timer, 328.

Upon receipt, the chip 30 of the supply item decrypts the formulation ofthe request in a manner similar to the way in which it was created. Thatis, the chip 30 performs an AES or TDES decryption, including keywhitening as appropriate, 330, for as many times undertaken by the chip60 at 322. The chip of the supply item next compares the plurality ofselect bits from the result of the decryption to the same plurality ofselect bits it received in the clear from the imaging device, 332. Ifthe bits match, 340, then the chip 30 of the supply item sends back tothe imaging device its formulated response, 342. The response 342includes the decryption result and the quanta amount requested from thecontroller at 318. The response 342 is initially sent to the controller,then to chip 60 according to the I2C protocol. At 344, the chip 60 thenverifies whether or not the response from the supply item wasappropriate, such as formatting. If so, the chip 60 approves this to thecontroller. If not, corrective action is taken at 312. Similarly,corrective action is taken at 312 if no match exists at 340 in thecomparison of the select bits of the decryption and the select bits inthe clear.

With reference to FIG. 3C, the controller next determines whether or notthe quanta provided from the supply item arrived within time, 350, asset by the timer started by the controller at 328. The value of thetimer can be any, but corresponds to 310 msec in one embodiment and thecontroller knows it by accessing the timer value 55 from its storedcertificate 59 (FIG. 1). At 352, the controller next determines whetheror not the amount of quanta returned from the chip of the supply item at342 matches the amount of quanta originally requested by the controllerat 318. If the controller requested 100 quanta, 100 quanta should be theamount returned from the supply item. If no match occurs, thencorrective action can be undertaken by the imaging device at 312.Likewise, corrective action can be undertaken by the imaging device ifthe quanta response from the supply item does not occur in time at 350.The controller also can reverse the order of its determinationsregarding time 350 and quanta matching 352.

At 354, the controller and the supply item next tally the amount ofquanta provided from the supply item to the imaging device. That is, ifthe original quanta=4,374 from the SCert, and the amount of quantarequested from the imaging device at 318 was 100 quanta, then both theimaging device and the supply item decrement the requested quanta fromthe original quanta, or 4,374−100=4,274 quanta remaining. They both saveoff that response in memory. Upon a next request for additional quanta,say in the amount of 150 quanta, the response in memory starts thetallying at 354 such that the quanta remaining is 4,124=4,274−150. Theprocess continues until, eventually, insufficient quanta remains withthe supply item and the supply item cannot return to the imaging devicean appropriate amount of quanta. This indicates to the controller an endof the allowed usage of the supply item.

At 356, the imaging device converts to authorized usage the quanta itreceived from the supply item and increases the authorized usage in theimaging device, 358. From the supply certificate, earlier loaded in theimaging device at 304, the imaging device knows that the multiplier Mcorrelates the mass of the toner to the quanta, e.g., M=50 mg oftoner/quanta. In turn, quanta times the multiplier results in mass ofthe toner. If the imaging device requested 100 quanta from the supplyitem and that same amount of quanta was returned to it, then Q×M=100quanta×50 mg of toner/quanta=5000 mg of toner. Further, from the storedcertificate 59 in the imaging device (FIG. 1), an additional multiplier53 exists that makes known to the imaging device a correlation betweenthe mass of toner to imaging pixels. The value of the multiplier ispredetermined and is calculated from imaging standards such as ISO pagesand types of toner. In turn, if multiplier 53=751,880 pixels/mg oftoner, the authorized usage αu in imaging pixels made available by therequested additional quanta is: multiplier 53 of the stored certificatetimes (Q×M), or αu=751,880 pixels/mg of toner×5000 mg oftoner=3,759,400,000 pixels. With reference to FIG. 4, the authorizedusage in the imaging device is seen as increasing 358, such as at time(t3), and the metered usage mu is again relatively far 359 from thecloseness threshold. Imaging continues and the process repeats until themetered usage eventually, again, reaches the threshold. In turn, thisforces the request for additional quanta from the supply item in orderto increase the authorized usage of printing in the imaging device.After many cycles of repeating this, the supply item runs out of quantathat it can give to the imaging device, thereby indicating an end oflife. It is intended, however, that the imaging toner of the tonercartridge actually run out before the quanta runs out so that users oftoner cartridges consume all of the imaging toner of the supply item.The quanta amount also should be close to being exhausted shortly afterthe toner runs out so that refillers and remanufacturers of tonercartridges cannot simply add more toner to the housing of the cartridgeand still have remaining quanta in the supply certificate, therebyallowing more authorized usage. Of course, other schemes are possible.

With reference to FIG. 5, installation of the supply item in the imagingdevice causes an initialization process to occur so that propercommunications channels are established between the two and that thecontroller knows it can trust the supply item. As part thereof, theimaging device first requests 502 and receives 504 from the supply itemthe firmware version of the supply item as it resides in memory 40, suchas at FWV 42 (FIG. 1). The controller requests this in an unencryptedmanner to informally check the presence or not of any and all supplyitems on the communications bus and to ascertain that they areelectrically connected and ready for further communications. Uponreceipt, the imaging device next checks the software features availableto the supply item by correlating the number of the firmware version toa stored reference indicating the same, 506. The imaging devicereferences this from its stored certificate or from elsewhere, such asat local or remote memory.

Next, the imaging device establishes more formal communications with thesupply item by starting an initialization session 508. It then requests510 and receives 512 from the supply item an encrypted instance of thesame firmware version FWV of the supply item it earlier requested andreceived in the clear. That the firmware version FWV is now encrypted,communication between the controller and the chip of the supply itemtakes place by way of the liaison function of chip 60 of the imagingdevice (FIG. 2). Upon the chip 60 notifying the controller of theimaging device that the response from the supply item is trustworthy,the controller again correlates the firmware version FWV of the chip ofthe supply item to relevant software features by referencing its storedcertificate, 514. At 516, the imaging device next confirms whether ornot both the unencrypted instance of the firmware version and thedecrypted version of the encrypted instance of the firmware version fromthe supply item match one another. If so, imaging operations canproceed, 518. If not, corrective action can take place at 312 totroubleshoot why the firmware versions do not match one another.

Similarly, FIG. 6 also notes the initialization process between thesupply item and imaging device so that proper communications channelsand trust are established between the chip 30 and controller C. As partthereof, the chips 30, 60 of the supply item and the imaging device swapor exchange their device certificates with one another, 602. They do sofirst in the clear (unencrypted) to establish an informal handshake withone another, verifying the device certificate received from the other.That the communications bus is configured with the controller of theimaging device being a master and each of the chips 30, 60 being slaves,the unencrypted device certificates swapped with one another are passedthrough the controller of the imaging device and whereupon they arecached at 604. Next, the controller of the imaging device requests 606and receives 608 from the supply item an encrypted instance of thedevice certificate 44 of the supply item 30 (FIG. 1). At 610, theimaging device confirms whether or not both the unencrypted instance anddecrypted instance of the encrypted instance of the device certificatesfrom the supply item 30 match one another. If so, imaging operationstake place at 612. If not, corrective action is undertaken at 312.

The foregoing illustrates various aspects of the invention. It is notintended to be exhaustive. Rather, it is chosen to provide the best modeof the principles of operation so one skilled in the art can practicethe invention without undue experimentation. All modifications andvariations are contemplated within the scope of the invention asdetermined by the appended claims. Relatively apparent modificationsinclude combining one or more features of one embodiment with those ofanother embodiment.

The invention claimed is:
 1. A method of setting up electricalcommunications between an imaging device and a toner cartridge that isphysically configured for installation in the imaging device, theimaging device having a controller, such as an ASIC, microprocessor,circuit, or combination thereof and a first chip in communication witheach other and the toner cartridge having a second chip configured toelectrically communicate therewith, the second chip of the tonercartridge having a memory storing a firmware version identifying acurrent version of firmware in the second chip and a device certificateidentifying the second chip, comprising: configuring the second chip ofthe toner cartridge to receive one or more requests for the firmwareversion and the device certificate from the imaging device; andconfiguring the second chip of the toner cartridge to provide to theimaging device both an unencrypted and encrypted instance of thefirmware version and the device certificate, wherein the devicecertificate includes a device unique public key signed by a global key.2. The method of claim 1, further including determining whether a matchexists or not between the unencrypted instances and decrypted instancesof the encrypted instances of the firmware version and the devicecertificate to allow or not imaging operations of the imaging device. 3.The method of claim 2, further including providing the encryptedinstances of the firmware version and the device certificate afterproviding the unencrypted instances of the firmware version and thedevice certificate.
 4. The method of claim 3, further including cachingthe unencrypted instances of the firmware version and the devicecertificate.
 5. The method of claim 4, further including passing theencrypted instance of the device certificate of the second chip of thetoner cartridge from the controller to the first chip of the imagingdevice.
 6. The method of claim 1, further including receiving at thesecond chip of the toner cartridge a device certificate of the firstchip of the imaging device.
 7. The method of claim 1, further includingconfiguring the second chip of the toner cartridge to receive a devicecertificate of the first chip of the imaging device.
 8. The method ofclaim 7, further including exchanging encryption keys between the firstand second chips.
 9. A method of setting up electrical communicationsbetween an imaging device and a toner cartridge that is physicallyconfigured for installation in the imaging device, the imaging devicehaving a controller, such as an ASIC, microprocessor, circuit, orcombination thereof and a first chip in communication with each otherand the toner cartridge having a second chip configured to electricallycommunicate therewith, the first chip of the imaging device having afirst device certificate identifying the first chip and the second chipof the toner cartridge having a memory storing a firmware versionidentifying a current version of firmware in the second chip and asecond device certificate identifying the second chip, comprising:providing from the second chip of the toner cartridge to the imagingdevice unencrypted instances of the firmware version and the seconddevice certificate; exchanging said first and second device certificatesbetween the first and second chips to verify trust there between; andthereafter, providing from the second chip of the toner cartridge to thecontroller of the imaging device an encrypted instance of the firmwareversion and the second device certificate, wherein the devicecertificate includes a device unique public key signed by a global key.10. A chip for installation with a toner cartridge having imaging tonerto be installed in an imaging device and configured for communicationwith a controller, such as an ASIC, microprocessor, circuit, orcombination thereof of the imaging device on a slave node of an I2Ccommunications bus while the controller is configured on a master nodeof the I2C communications bus, comprising a memory storing a firmwareversion and device certificate and one or more keys to provide both anencrypted and unencrypted instance of the firmware version and thedevice certificate to the imaging device upon installation or receivingrequests from the imaging device, wherein the device certificateincludes a device unique public key signed by a global key.
 11. In atoner cartridge configured for installation in an imaging device havinga controller, a method of tracking lifetime of the toner cartridge,comprising: storing in memory of a chip configured for installation withthe toner cartridge a first value representing a firmware version of thechip and a second value representing a device certificate; andconfiguring the chip to receive from the controller a query forunencrypted and encrypted instances of the firmware version and thedevice certificate, wherein the device certificate includes a deviceunique public key signed by a global key.
 12. The method of claim 11,further including providing from the chip to the controller bothunencrypted and encrypted instances of the firmware version and thedevice certificate.
 13. A chip for installation with a toner cartridgehaving imaging toner to be installed in an imaging device and configuredfor communication with a controller of the imaging device, comprising amemory storing a firmware version and device certificate and havingaccess to one or more keys to provide both an encrypted and unencryptedinstance of the firmware version and the device certificate to theimaging device upon installation or receiving requests from the imagingdevice, wherein the device certificate includes a device unique publickey signed by a global key.